Pre A interior light lense

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Doug Naef
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Joined: Mon Aug 23, 2010 11:47 pm
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Pre A interior light lense

#1 Post by Doug Naef »

I have looked on the forum for a plain interior lense. I saw that someone suggested TheSamba but I found nothing there. Can anyone give me a good reference? This is for an early '53 that does not have the switch on the housing. I need two of them. Thank you, Doug
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Rick Albro
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Re: Pre A interior light lense

#2 Post by Rick Albro »

Doug, several people make these lenses there are also several opinions about what is right. Every original one that I have seen is flat and thin. There is no texturing on the inside. Many European car seem to have replacement that do have a textured lenses. I think the textured lenses were made for VW's of a similar vintage. The main problem with the ones being made is that if the color is right the thickness and texture is wrong or if the thickness is right the color is to white! I looked at making these but the lens is very thin and the original lens was vacuum formed. I think Tom Birch makes a good profile and the right thickness but the color is to white. There are people on the samba that also sell lenses. I like Tom Birches lenses the best even if the color is a bit off. Tom's email is on his web site http://www.356splitregisrty.org/ If Thomas is not available there are several people that are probably interested in making a small run of these.
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lenses.jpg
PreA cab dome light.jpg
dome light.jpg
coupe lights.jpg

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Doug Naef
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Re: Pre A interior light lense

#3 Post by Doug Naef »

Thank you very much for the information. The white is definitely not correct. One would think in today's world of plastics that someone would have a more amber colored piece that could be easily formed. If I can find an original or correctly sized reproduction I may look into a small low cost run. Thank you again. Just hoping someone has already figured it out!

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Rick Albro
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Re: Pre A interior light lense

#4 Post by Rick Albro »

Doug,
You have not included your email address in your profile. I measure the original lens to be 0.022" thick while the lens from the samba is 0.030" and the lens from Thomas Birch which has the best profile is 0.050" thick. This lens really should be vacuum formed and I believe that Thomas and the vendor from the samba do make theirs this way. An alternative is to cast the lens where you can control the tint and therefore the color. The problem is that with a cast resin the viscosity increases as the material cures. The viscous material tends to be coherent and does not "fill" fine details, cracks or pores... a 0.022" lens thickness starts to fall into this category where the cast material does not want to flow into the mold and will often be incomplete. I have discussed this issue with the folks down the street that make props for Hollywood. They usually don't make things that are as small as the parts that I have been casting. From previous discussions if you use the 0.022" thickness to make the lens you really need to update the bulb to one of the LED converted bulbs or the new lens will melt just like the original. The led bulbs are easy to make or can be purchase outright for those not wishing to do their own construction. My contact information is in my profile.

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James Davies
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Re: Pre A interior light lense

#5 Post by James Davies »

Rick & Doug,

I have an original one of these lenses too (melted), and it is yellowed over time. But it is quite opaque. I suspect the original color is opaque white. The bulb produces yellow light, so the effect is yellow. Both pristine originals I've seen in unrestored, low-mileage cars have been white. See photo below.

As for profile, the Samba repro one looks to be the most correct one to me. It's longitudinal profile matches your and my original Rick, at least from your photos.

I also have a no-name reproduction of this lens that is not opaque (enough) but is quite thin. Not sure who made this one. I'm not happy with it, so I would be happy to find another supplier. I think the Patereks had a repro of this lens at some point. It looked good. I don't know who made it.
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_23_0906 copy.jpg
20141218_40d_3763f copy.jpg

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Rick Albro
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Re: Pre A interior light lense

#6 Post by Rick Albro »

James is right in that the original lens was certainly not yellow or brown. The lens is thin so that the bulk of the lens is susceptible to oxidation. There have always been several people making these at different times and the vacuum technique used to form this lens is not shared with other parts so either you are set up to do this or not. I think the transparency comes from the thinness and not the opacity of the material. The real challenge here is to find the right material and have someone who is already doing this make up a small run. Perhaps if we start collecting names of people who would commit to buy a lens the people who can do this will be "inspired" to make these available. I have what I showed in my pictures to make molds from so there are good examples to work with. I am happy to commit to buy at least one lens even though I have a collection of the available lenses. I would be slow to criticize anyone who steps up and tries to makes these, some parts are not trivial to make. I would also be happy to lend out my lenses for dimensions but I suspect that the people who have the equipment set up probably already have original lenses to work form. I can try to dig up the contact for the samba source if needed or we can just ping Everett Barnes he has always responded and he has posted on the Registry before.

Awesome pictures James, once again you show why you are a pre A Guru!

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